[Ultrastructural studies on invasion of inner limiting membrane by malignant tumor cells]

In order to observe the process of invasion, retina of rat was used as a model to substitute the inner limiting membrane of retina for the basement membrane. Retina invaded by esophageal carcinoma cells and B16 melanoma cells upon the inner limiting membrane was studied by scanning and transmission electron microscopy. The results showed that the inner limiting membrane was destroyed by the two kinds of tumor cells mentioned above. The process of destruction was followed by a series of transformation in the inner limiting membrane, i.e. folding, swelling, thickening, and granulation. The inner limiting membrane was dissolved focally as a result of transformation, and then tumor cells invaded the retina through these dissolved regions. It seems that, like a barrier, the inner limiting membrane plays a similar role as the basement membrane.